Conventionally, magnetron sputtering apparatus for single substrate processing used for manufacturing information recording disks such as compact discs (CDS) or digital video discs (DVDs), the disk substrates are fixedly positioned opposing to the target which was provided in the vacuum chamber that composes the sputtering chamber. Sputtering was carried out through the masks fixed in the reaction chamber separately from the disk substrates, to cover the center portion and periphery portion of the disk substrates.
On the other hand, in the sputtering of MO (Magnet-optic) disks, the center masks and outer masks are previously attached to the disk substrates. Sputtering was carried out with the disk substrates rotating, after these mask-attached disk substrates are transported into the sputtering chamber of the sputtering apparatus.
However, one problem is that the composition distribution of the film formed at the surface of disk substrates, especially the distribution uniformity along the circumference and along the diameter of the disk substrate is not adequate, so it is impossible to form a film with satisfactory characteristics.
It is because in conventional magnetron sputtering apparatus used for manufacturing CDs or DVD disks, that sputtering is carried out under such condition that the disk substrates arranged in the sputtering chamber are fixed and do not rotate on the central axis of the disk substrate.
On the other hand, in conventional MO disk sputtering, the film thickness uniformity along the rotating direction is good because the sputtering is carried out while the disk substrates are rotating. But it has the drawback that attaching and detaching mechanism of masks to and from disk substrates or transporting mechanism are necessary to make mechanisms and process complicated because the disk substrates previously furnished with the center masks and the outer masks are transported into the sputtering chamber.
Besides, it had a drawback that when detaching masks from the disk substrates, sputtered film deposited on the mask is pealed off to contaminate disk surface film resulting in the decrease of product yield.
The purpose of this invention is to provide such apparatus capable of furnishing disk substrates with masks without complicated mechanisms and complicated process, and capable of sputtering during rotating the disk substrates on the central axis.